1. Technical Field
The technology described herein relates generally to wireless networking. More particularly, the technology relates generally to determination of when a transmitting device of a wireless network may transmit using a process known as Clear Channel Assessment (CCA).
2. Description of the Related Art
A WLAN is being standardized by the IEEE (Institute of Electrical and Electronics Engineers) Part 11 under the name of “Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications.” A series of standards have been adopted as the WLAN evolved, including IEEE Std 802.11™-2012 (March 2012) (hereinafter, IEEE 802.11). The IEEE Std 802.11™-2012 was subsequently amended by IEEE Std 802.11ae™-2012, IEEE Std 802.11aa™-2012, IEEE Std 802.11ad™-2012, and IEEE Std 802.11ac™-2013 (hereinafter, IEEE 802.11ac). These standards are each hereby incorporated by reference herein in their entirety.
In 802.11, CCA is performed by a transmitting device. When a station (STA) wants to transmit a packet, it checks for RF energy in the medium and performs CCA to ensure that there is not any other STA transmitting a packet. As part of CCA, the station may check a Network Allocation Vector (NAV) sent as part of a prior transmission from another station. The NAV indicates a period of time when the other station is using the medium either to send or to receive packets.
However, CCA performed as described above may prevent the medium from being used to its full capacity. Accordingly, a process for determining whether a first transmitting device can communicate with a first receiving device without interfering with contemporaneous communications between a second transmitting device and a second receiving device is desired.